this horrendous person cannot be billed or called a human being. he is asura in the form of a human called abu salem. no capital punishment is enough for this asura. his karma will consign this asura to his fate.
the Indian Govt as given their word of assurance to the Govt.of Portugal, should follow and keep their word.
Justice should be done while this demon is alive, that is to give him the most rigorious punishment and put him into exile (solitary confinement) and after this justice is passed, then this demon's karmas will surely follow him. Every asura and human has to depart and leave the body.So solitary confinement is and should be for this demon and all the other demons who are amongst us in India, which outnumber the honest. All inhuman demons born are and will be consigned to hell.